[PATCH] D20147: [WIP] DebugInfo: New metadata representation for global variables.

[Mehdi Amini via llvm-commits]

I agree with you on llvm-ar.
For ThinLTO it is totally different and the symbol table does not help: when you want to import a function, you need to lazy-load the module and materialize the functions you want to import.
This is where we want as much laziness with other globals and more importantly metadata in general.

> On Jun 2, 2016, at 4:29 PM, Peter Collingbourne <peter at pcc.me.uk> wrote:
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> pcc added a comment.
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> While it's possible that that would result in a performance improvement, it's unclear that that would be the case, and I don't think we should make such a change without evidence. For ThinLTO and llvm-ar a more effective performance improvement would be to pre-compute the symbol table (see pr27551), which would avoid the need to read most of the bitcode file. There's also the possibility that lazy loading GlobalVariables would slow things down, as the benefit of lazy loading globals would generally be less than for functions.
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> http://reviews.llvm.org/D20147
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>